We will continue our study of the use and limitations of serial CEA assays (1) in the early detection of recurrent cancer (colon, stomach, pancreas) following surgery and (2) as a monitor of chemotherapy and radiation therapy. Elevated CEA levels sometimes seen in patients without malignancy may be due to hepatic failure to degrade and/or secrete CEA. We will study the liver metabolism and excretion of CEA-active glycoproteins (and other tumor markers) and their effects on CEA levels in the circulation, digestive juices (bile and pancreatic juices), and in ascites and other effusions. Immunochemical identification, characterization, and quantification of the CEA-active substances in these fluids, secretions and effusion are necessary in order to develop assay methods which will detect and differentiate among the numerous primary and metastatic adenocarcinomas which produce them. Other tumor markers, including alpha-fetoprotein, and the zinc glycinate marker will also be studied. BIBLIOGRAPHIC REFERENCES: Zamcheck, N., Doos, W.G., Prudente, R., Lurie, B.B. and Gottlieb, L.S.: Prognostic Factors in Colon Carcinoma: Correlation of Serum Carcinoembryonic Antigen Level and Tumor Histopathology. J. Human Path., 6:31-45, 1975. Lurie, B.B., Bull, D.B., Zamcheck, N., Steward, A.M. and Helms, R.A.: Diagnosis in Colon Cancer Based on a Profile of Immune Reactivity. J. Nat. Cancer Inst., 54:319-325, 1975.